Overriding a classes paintevent function when its called from within a class.
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Hi, How would you go about overriding the paintevent of a class when its called within another class.
e.g.
@
myClass::myClass(QWidget *parent) : QWidget(parent)
{
this->progressBar = new QProgressBar(this);
}
@I wish to override the progressBar paintevent from within the myClass class.
Thanks.
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Hi,
I'm not sure what you want to do. If you want to override the panitEvent of the QProgressBar you will have to derive a subclass from it and use that.
bq. I wish to override the progressBar paintevent from within the myClass class.
So you want to provide an implementation to overrider method x which is a member of class A from method y which is a member of class B. C++ is renown to allow all sort of fuzzy stuff, but I still doubt that is possible.
Or didn't I get you point?!?
Best
Soraltan
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It is possible in Qt, because it is an event. Events can be intercepted by using an eventFilter. To do that, you do something like this:
@
myClass::myClass(QWidget *parent) : QWidget(parent)
{
this->progressBar = new QProgressBar(this);
progressBar->installEventFilter(this);
}bool myClass::eventFilter(QObject* o, QEvent* e)
{
if (o==progressBar && e && e->type() == QEvent::PaintEvent) {
//handle the paint event for the widget
return true; // if you want to stop the original paint event from arriving
}// call base class implementation return QWidget::eventFilter(o, e);}
@However, I think that it is probably the wrong way to do whatever you want to achieve. I think you should probably subclass QProgressBar, use a custom style on the progress bar, or use a style sheet on it. It depends on what you want to achieve, and there may be more than one way to do it.